Multi-layer pipe assemblies are commonly utilized to convey oil, gas, and/or other suitable fluids. In particular, such pipe assemblies are employed in the oil and gas industry, such as in subsea applications as well as in oil and gas production fields. In subsea applications, for, example, multi-layer pipes may be utilized in risers, transfer lines, umbilicals and/or other suitable pipe assemblies. In production field applications, multi-layer pipes may be utilized in risers, infield flow lines, export pipelines and/or other suitable pipe assemblies.
Multi-layer pipe assemblies, and the pipe sections thereof, typically include at least two layers; a hollow body or inner layer, and a barrier layer or outer layer generally surrounding the hollow body. Other layers may further be included generally surrounding the barrier layer. Various materials have been utilized to form each of these layers, in an effort to improve various performance characteristics of the resulting pipe sections. Additionally, these layers have been bonded together or left unbonded, depending on the application and the desired performance of the pipe section. For example, U.S. Pat. No. 5,876,648 discloses a pipe section having a metal inner layer and an outer layer formed by particular shrinkable polymers. U.S. Pat. No. 6,039,083 discloses a pipe section having a metal inner layer and an outer layer formed by particular polymers. U.S. Pat. No. 8,210,212 discloses a pipe section having a metal inner layer and a polymer outer layer. U.S. Pat. No. 8,163,364 discloses a pipe section having a polymer layer and a film layer. U.S. Patent Application No. 2009/0301594 discloses a pipe section having a metal inner layer and an outer layer formed from a polyphenylene sulfide (PPS). U.S. Patent Application No. 2010/0326558 discloses a pipe section having an inner layer and a polymer outer layer. U.S. Patent Application No. 2011/0041947 discloses a pipe section having a thermoplastic inner layer and a tape outer layer bonded to the inner layer. Japanese Patent No. 3021435 discloses a pipe section having a thermoplastic inner layer and a tape outer layer.
However, the materials utilized in such known pipe assemblies do not provide the characteristics required for many applications. For example, in many cases, particularly when metal hollow cores are utilized, the barrier layers remain unreinforced. Thus, the strength of the overall pipe section may be limited. In many cases, additional layers are added, surrounding the barrier layer, to strengthen the pipe section. However, such additional layers add weight to the pipe section and reduce the flexibility thereof.
Accordingly, improved pipe sections and assemblies formed from such pipe sections are desired in the art. In particular, pipe sections that utilized barrier layers which provide increased strength to the overall pipe section are desired. Lightweight pipe sections with increased strength and flexibility would be particularly advantageous.